Nortel ISDN Signaling Link, Описание, установка и эксплуатация

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Page 120 of 378 ITG Engineering Guidelines
553-3001-202 Standard 1.00 April 2000
Serialization delay
This is the time it takes to transmit the voice packet one bit at a time over a
WAN link. The serialization delay depends on the voice packet size and the
link bandwidth, and is given by the following formula:
Serialization delay in ms = 8*(IP packet size in bytes)/(link bandwidth in
kbit/s)
Table 21 shows what the serialization delay for voice packets on a 64kbit/s
and 128kbit/s link. The serialization delay on higher speed links are
considered negligible.
Table 21
Serialization delay
Codec Frame
duration
Serialization delay
over 64kbit/s link
(ms)
Serialization delay
over 128kbit/s link
(ms)
G.711A/
G.711U
10 ms
14.00
0.88
20 ms 24.00 1.50
30 ms 34.00 2.13
G.729A/
G.729
Annex AB
10 ms 5.25 0.33
20 ms 6.50 0.41
30 ms 7.75 0.48
G.723.1
5.3 kbit/s
30 ms 6.50 0.41
G.723.1
6.3 kbit/s
30 ms 7.00 0.44